feat: implement input length constraints and enhanced validation for international phone numbers

libs/api/src/lib/features/licensing/licensing.helpers.ts

@@ -1,3 +1,4 @@
+import { isValidPhoneNumber } from 'libphonenumber-js';
 import { resolveTokenFromStorage } from '../../session';
 import type {
   Bilingual,
@@ -526,6 +527,13 @@ export function validateSections(
       }
       if (empty) continue;
 
+      // PhoneInput emits E.164 while typing, so a half-typed "+2519" is a
+      // non-empty string that still has to be caught here.
+      if (field.type === 'PHONE' && !isValidPhoneNumber(String(value))) {
+        errors[`${section.key}.${field.key}`] = 'Enter a valid phone number';
+        continue;
+      }
+
       const numeric = Number(value);
       if (!Number.isNaN(numeric)) {
         if (field.min !== undefined && numeric < field.min) {